09-18-2007 12:01 PM - edited 03-05-2019 06:33 PM
Here's a short version of the question:
If VTP pruning appears to be "pruning" on all of your trunk links to other switches except for one -- what could be a possible cause?
Far-end switch is in the same VTP domain with adequate code level and only a few ports not in the native vlan (with the exception of a trunk port to a Cat2950)?
09-18-2007 10:33 PM
Is CDP working corrrectly on that link?
Is the trunk statically on, or dynamic?
Kevin Dorrell
Luxembourg
09-19-2007 12:24 PM
Kevin,
It appears that the culprits were non-Cisco IP phones that were trunked on a far-end switch.
I'm now assuming that trunks to non-Cisco devices from a downstream switch will cause all upstream trunks not prune (which kind of makes sense).
09-19-2007 01:11 PM
Oh right, that does make sense. If you have a downstream trunk and you cannot find out what VLANs it wants, then you cannot justify pruning any VLANs on the upstream trunks.
Now, if you had restricted the allowed VLANs on those non-Cisco trunks by configuring an allowed vlan list, would it have pruned the rest?
Thanks for that ... it's a good one to remember.
Kevin Dorrell
Luxembourg
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